fix(ui): show <1m for sub-minute quota reset windows instead of 0m (#108009)

* fix(ui): show <1m for sub-minute quota reset windows instead of 0m

formatQuotaReset computed Math.floor(diffMs / 60_000) for the minute branch.
When a provider quota window resets in under 60 seconds (common for 5h Anthropic
or 3h Codex windows near rollover), the floor is 0 and the UI rendered
"Resets in 0m" — nonsensical and indistinguishable from "already reset".

Add a sub-minute guard returning "<1m", matching the convention already used
by formatRemainingShort and formatRelativeTimestamp elsewhere in the codebase.

Co-Authored-By: Claude <noreply@anthropic.com>

* test(ui): cover quota reset display boundary

Co-Authored-By: ZCode <noreply@zcode.ai>

* test(ui): cover elapsed quota reset boundary

Co-Authored-By: ZCode <noreply@zcode.ai>

---------

Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: ZCode <noreply@zcode.ai>

ui/src/lib/provider-quota-summary.test.ts

@@ -15,6 +15,16 @@ describe("formatQuotaReset", () => {
     expect(formatQuotaReset(Date.now() + 2 * 60 * 60_000 + 15 * 60_000)).toBe("2h 15m");
   });
 
+  it("returns <1m for sub-minute reset windows instead of 0m", () => {
+    vi.spyOn(Date, "now").mockReturnValue(Date.parse("2026-05-30T12:00:00.000Z"));
+
+    expect(formatQuotaReset(Date.now() - 1)).toBe("now");
+    expect(formatQuotaReset(Date.now())).toBe("now");
+    expect(formatQuotaReset(Date.now() + 1)).toBe("<1m");
+    expect(formatQuotaReset(Date.now() + 59_999)).toBe("<1m");
+    expect(formatQuotaReset(Date.now() + 60_000)).toBe("1m");
+  });
+
   it("ignores Date-invalid reset timestamps", () => {
     expect(formatQuotaReset(8_640_000_000_000_001)).toBeNull();
     expect(formatQuotaReset(Number.POSITIVE_INFINITY)).toBeNull();

ui/src/lib/provider-quota-summary.ts

@@ -12,6 +12,9 @@ export function formatQuotaReset(resetAt?: number): string | null {
     return "now";
   }
   const minutes = Math.floor(diffMs / 60_000);
+  if (minutes < 1) {
+    return "<1m";
+  }
   if (minutes < 60) {
     return `${minutes}m`;
   }